Automatic control means for air-pressure pumps.



II. Ix. RUSSELL. A Auowmfcowmm MEANS FOR AIR PRESSUREPUMPS. APPLICATIONFILED NOV. 27 I9I5.

l Patented Jun@ I2, Ism.

1 I. I wITNEssI-:s [gf/ ATTO Fl N Er .Which may be oit relatively smallsize as compared to the cylinder of the pump l, and the bracket 9 may hesecured to the cylinder ,10 by screws 1l or otherwise, being in turnconnected to the cylinder of the punp 1 by screws 12 or in any suitablemanner.

As shown the cylinder 10 is et even dian1- eter throughout with one endinternally screw-threaded, as indicated at 1B and the y other endexternally screw-threaded, as in- .dicated at le, and in the usualinstalled position of the device the end with the threads 13 may beconsidered as the' upper end and y the end with the threads ll may heconsidered as the lower end. Applied to the screw threads le is acylinder head l5 having a central hoss 16 and an axial passage 17extending through the hose lo. The l1n.-

-ner face of, the head i5 may he somewhat (lished, as indicated at 18,andv confined between the head and the corresiioiiulingg end of thecylinder 10 is a dish or diaphragm 19 'offlexible material, such asleather. or some niat-erial of like function for the purposes of theinvention. lfinterineF the' passage li' is one end ot' a pipe 20, theother end of which is connected to the outlet pipe 3 of the pump l. Thepipe 2O is in :ree conununication with the passage 17' and the pipe 3,and, therefore. in the space between the. diaphragm 19 and the face 18or" the head l5 there is always established an air pressurecorresponding to the pressure within the pipe 3.

Located Within the cylinder l0 is a piston 2l which may'i tit theinterior ot' the cylinder with a certain freedom, whereby the piston isnot subjected to any particularlg.' .trictional resistance in itsmovements in the cylinder 10. This piston has a slightly con- Vex face22 presented toward the diaphragm 19. Connected at one end tothe piston21 is a piston rod 23 extending lengthwise of the cylinder and through acylinder head 2e exterior-ly threaded end applied' to the threaded endi3 of the cylinder l0. Bear ing at one end against the piston Q1 and at.

the other end against the head :24 is a coiled spring Q5 tending at alltimes to maintain the piston 2l against the diaphragm 19. lVhen thespringr is lodged within the cylinder 10 and the head 24 is applied,such head is screwed along the threads 13 until the si'iriner is underapredetermined coinpression. which conipiession may be varied hy screwingthe head Qi.- in the appropriate of the diaphragm it) toward the headl5, and

this air `pressure increases sufiicieiltly the piston 2l is moved in adirection 'to further compress the spring 25, and when the air pressureis reduced suiliciently the expansive force ofthe spring 25 overcomesthe air pressure so that the piston 2], is restored to its first'position. The diaphragm l!) being made of i'ienible material readilyyields to the variations ci. air pressure, and yields suicient tor thepurposes of the present invention. The head 24 is provided with a hub 26exteriorly shaped for the application of a 'tool to facilitate theadjustment oit the head.

Rising from the hraclret 9, and preferably though not necessarily inone'piece vtherewith, is a post 27 extending tor an appropriate distanceabove theoylinelerl0, and

this post may be hifureated at its upper end and there carries a rocklever 28 haring an arm 29 extending over the cylinder lO'dianietricallythereoii, and another arm it@ erltending over the pump cylinder so thatits free end overrides the head 'l' of the stein 5 of the relief valve.Extending' laterally from the post in a direction away from the cylinderl() is an erin 3l having ln angle extension 32 risingr from the end ofthe arm remote froin'the post 27 and in sub stantial parallelism withthe post'27.v he extension 32 extends to a less height than the post 27and at its upper end carries, oy

means of a. pivot pin or screw 33, a latch lever haring.;l at one end anose 35 and at the other end provided with ay pin 36 to which isattached one end of a coiled spring 37, which in turn has its other endsecured to pin 38 on the arni 3l. The arrange nient is such that the arm30 of the lever 28 may strike the nose 35 on movement toward the pin 33or extension 32,*and this nose being appropriately rounded is forced outof the Way oil the arm 30, the spring 37 then yielding. Asvsoon as thearin 250 has moved beyond the nose 35 in its travel tol ward theextension 33, the reaction ci" the,4

spring 3T causes the nose to snap-eter the arm, thus locking or latchingit against return movement.

F ast to the cylinder l() at a point diarnet Arically opposite lroin'the post 27 is another post 39 which may he secured to thecylinder hyscrews Lt0 or otherwise, and this post rises to about the height of theextension B2 of the arm 31, although such particular proportions are notobligatory.

Carried by the post 3f? near its upper end is a latch lever el, piyoted'to the post hy kis connected by a pin 4G insegne a screw or pin 42. Oneend oi the latch lever 4l, which is shown separately in Fig. 6, isprovided With a nose 43, while the other end ofthe latch lever carries apin 44 to which is secured one end of a coiled spring 45, and the otherend of this coiled spring to the post 39. The latch levers '34 and 4lmay be practically identical in form, and the latch or latch lever 4l isdesigned to engage the free end of the arm 29 of the lever 28 when movedsulliciently towardV the upper end of the post 39.

Carried by the post 27 below the lever 28 is another lever 47 pivoted tothe post 27 by a pivot vscrew 48 or in any other appropriate manner. mayterminate in a tapered extremity 50 moving alongside of the post 3f), soas to engage the latch lever 4l to rock the lever against .the action ofthe spring 45 for a purpose to be described. The lever 47 has anotherarm 5l lodged alongside of the ex- The lever 47 has an arm 4f) which. y

i tension in position to engage the latch' lever 34 to move it againstthe action of the spring 37 for a purpose to be described.: The arm 49of the lever 47 is connected by a screw or pin or otherwise to thepiston rod 23, which rises asuilicient distance above the head 24, andthis pivot connection pro vided by the screw 52 may be sullicientlyloose to permit the lever 47 to be rocked for an appropriate distance bya longitudinal movement of' the piston rod. The end 50 of the arm 49 isconnected to a corresponding portieri of the arm 27 by a coiled spring53,

' and the outer end ofthe arm 5l is connected and put under superiortension.

to a corresponding' portion of the arm 30 by a coiled spring .34.

The normal position of the parts when there is no air pressure Withinthe air pump, or such air pressure is less than the predeterminedmaximum, is that shown in l `ig.\2, except that the piston 2l may beconsidered as j ust beginning to rise under the air pressure, since inthe absence of any material air pressure the piston forces the diaphragmlll close against the face 18 of the head 15.

As the air pressure increases the di aphragm 19 is lifted, and with ittravels the head 2l compressing. `,the spring` 25. 'This movementcontinues until the end 50 of the, arm 49 has by engagement with thelatch 4l rocked it on its pivot 42 and the nose' 43 has been swung toone side out ot the path ol the arm 29 of the lever Qt. ln the meantimethe Varm 51 of the lever 48 has been moving away `from the arm 30 ot,the lever Q8 then held against movement by the vlatch 41 and the spring54 has been ci)rrespondingly extended Now, as soon as the latch nosii 43has released the lever 28, the reaction of the spring 54 is suflicientto move the valve 4 away from its seat,

,that now the lever thus opening the interior of thepressure side of thepump l to the atmosphere, and the pump l instead of increasing thepressure Within the pipe 3 discharges into the atmosphere. The rockingof the lever :2S due to the spring 54 has caused a movement ol the lever28 from its first position shown in full lines in Fig. 2 to the dottedline position shown in Fig. This movement is sul-ificient to bring thearm 30 of the lever 28 below the nose end 35 of the latch 34, which inthe meantime has been released by the movement of the arm 51 in adirection away from the pivot 33, so that when the arm 3() has movedpastl the nose 35 the latter snaps over the arm 30, thereby locking itagainst return movement so long as the latch 34 is held in the lockingposition by the spring 37 and is not acted upon by the arm 5l.

The lever Q8 when in the locked position last described positively holdsthe valve 4 open, and this without regard to the condition of pressurewithin the cylinder l() so long as such pressure is suflicient to holdthe arm 5l out of actuating engagement? with the latch 34.

As soon as sufficient. 'air has escaped through the opening unclosed bythe vvalve 4 under the conditions last described, the pressure withinthe'pipe 20 drops to a degree permitting the spring 25 to return the)iston 2l to its first position. This results ,in the release of thelatch 4l by the terminal portion 50 of the arm 49 and the movement olthe arm 5l into engagement with thc latch 34 actuating the latteragainst the tendency of the spring 37 until the nose 235 releases thelever 28. ln the meantime the return rocking movement of the lever 47basreleased the tension upon the spring 54 and increased the tensionupon the spring 5B, so 28 is strongly urged awav 'from the head 7 andtoward the latch 4l to which position it quickly moves and the nose 43of the latch 4l snaps over the arm 29, l

invention is to maintain a constant pressure' at the delivery side ot'the pump within narrow limits with the relielifalve actuating meanspositively locked in both limits ot its movement. Moreover, the actionof the opening and closing means forl the reliel valve is sudden andforceful, thereby preventing all chattering or uncertain action of therelief valve.

Yof o. cylindi-fr :issociutedl with the pump, o.

piston in the cylinder having e. piston rod iro'ectin! therefrom :i rochlever connected 'to the piston rod for actuation thereby, on other loverhaving one end in position. to engage the relief vulve and open it,spring connections between each end of the irstnamed lever and lthecorresponding ends of Athe second-named vlever, and letches'in the pathof the rst-nnined lever on opposite sides oi' its pivot and arranged inthe path of `the first-named leverfor actuation thereby.

2. The combination with s pressure-producin pump having e relief valve,of n cylin er associated wit the pump, e piston mounted in the cylinder,e spring in the cylinder tending to hold the piston et one limit of itsstroke, connections between the pressure side of the pump und thecylinder on the side of the piston remote 'from the spring, e piston roderried by the piston :ind extending to the exterior 'of the cylinder, e-roclr lever-connected' on one side of its pivot to the'piston rod,:mother roch lever linvingone end in position to engage' and open therelief volvo7 elastic connections between oppositerencls of thefirst-named lever andthe corresponding opposite ends of the second-namedlever, und latches in the peth oi the second-named lever on oppositesides' of its pivot and also in the path or' the iirstyiieined lever onopposite sides of its pivot sind operating; to elternetely lstch and vrelease the secondfnemed lever et the limits oii'its rocking movements,seid latches being in the psth et the first-named lever tor alternateactuation thereby to the unletcbed position.

.3. rlhe combination with :i pressure-pro# ducin pump having o. reliefvalve, of c 1 cyiin er associated with the pump, connections between thepressure side'o the pump andthe cylinder, e diaphragm in the cylinder inposition to be noted upon by luid under pressure entering the cylinderthrough the connections with the pump, e piston in .the cylinder on theside of the` diaphragm remote from lthe pressure connections, n

, spring in the cylinder' tending to move 4Vthe piston toward thediaphragm, e piston rod for the piston extending to the exterior of thecylinder, o. roclr lever connected to the piston rod for actuationthereby, latches in tliepeth ot the opposite ends of the rock lever forelternnte actuation thereby', enother rock lever havingits opposite endspositioned 'to move in alternation into enthe unletchin moonen gngementwith the latches, and springs beimporting to it e normal constraint inthe ,A

other directionra rock member controlled by` the pressure responsivemeans, another rock member adapted to open the relief valve, latches forthe second rock member in position to latch itiiit opposite extremes ofits movement, and spring connect-ions between the first-named rockmember and the second-named rock member on opposite sides oi' thenxis ofrocking of the rock members, 'the first-named rock member being inoperctive relation to the latches to ectuate them Iand timed in movementwith respect to the latches to put the second-named rock meini ber undertensionel strain to move in one direction or the other previous tounlstching it'to such movement.

5. A. device for the purpose described,

comprising e cylinder, a pistontherein, u

piston rod connected to the piston and of n. y y

length to extend beyond the cylinder, s. dia.- phrngm in the cylinder inposition to engage the piston, means yfor directing Huid u nder pressureagainst the diaphragm to move the piston, :i spring in the cylinder.-impertngto the piston a constraint in opposition to pressure establishedWithin the cylinder, e rock lever mounted exterior to the cylinder andconnected 'to the piston rod, another rock lever adjacent to thefirstnamed rock lever, springs connecting the corresponding ends of thetwo levers together, a. spring controlled latch lever in the path of oneend oi' the hist-named lever and havin e. latch nose in the path of thecorresponding end oi the second-named lever, `and another springcontrolled1 hitch lever having one end in the path of the other end ofthe rstnamed lever, and e nose inV the path of the corresponding end ofthe second-named lever,- Whereby rocking movements of the first-neinedlever to cause zi corresponding rocking of the secondnamed lever throughthe spring connections and seid` rocking movements of the rst-namedleverto cause of the second-named lever sitter the elestic tendency hasbeen imparted thereto. A

6. The combination with 'n pressure producing pump provided with crelief valve, of ineens responsive to fluid ressure pro- Vduced by thepump and including a member iio ioA

the reuk lever on opposite sides of the of rockiilg i'hereof.

En testimony that I claim the foregoing' es my own, I' have hereto uxedmy slgnatme in the presence of wo fitiiessea HARVEY J". RUSSELL.'

Witnesses 1 A. E. SEAI'JSTRR E. l?. RUSSELL.

